Automatic furnace heat regulator



Jane 21, 1936. P. c. TIMM ET AL 2,028,363

AUTOMATIC FURNACE HEAT REGULATOR Filed Feb. 5, 1954 2 sheets-sheen Jan. 21, 1936. P. c. TIMM ET AL 2,028,363

I AUTOMATIC FURNACE HEAT REGULATOR v Filed Feb. 5, 1934 2 Sheets-Sheet 2 Fig.7

3mm P.C.Timm W. PTimm Patented Jan. 21, 1936 UNITED STATES AUTOMATIC FURNACE HEAT REGULATOR Paul C. Timm and William PrTimm, Lincoln, Nebr.

Application February 3, 1934, Serial No. 709,643

14 Claims. (01. 23616) Our invention relates to furnace heat regulators, its primary object being the provision of mechanism for making the regulator as nearly automatic as it is possible to make it.

Another of. our objects is the provision of a double booster slide for temporarily increasing the furnace draft, the slide being automatically-operable for closing the draft and being automatically operable in response to thermostat control for opening the: draft. 1 4

Another of our objects is the provision of a support of novel structure for supporting the mechanism, the support being anchored at both extremities,

A very importantobject of our invention is the provision of means for automatically governing the heat of the furnace without allowing the furnace itself to heat past a'maximum predetermined point, thereby utilizing to the greatest possible extent all of the heat developed by the fuel.

Another object of our invention is the provision of a manual control for closing the check valve during refueling, means being provided for automatically opening the check valve at a pre determined maximum furnace heat. 7

It is a further object of our regulator to utilize external forces, electrical or spring driven means, toopen the draft valve and to close the check valve of the furnace at a predetermined minimum temperature, and to use the internal force of expansion of the furnace to automatically close the draft valve and to open the check valve at a predetermined maximum. furnace heat.

Having in view these objects and others which will be pointed out in the following description,

- We will now refer-tothe drawings, in which Figure 1 is a view of broken portions of the furnace with our automatic heat regulator installed thereon and with portions of the view being shown in diagrammatic form.

Figure 2 is a view inv isometric projection of the motor and of the switch mechanism con trolled thereby.

Figure 3 is a vertical sectional view through the double booster slide.

Figure 4 isa fragmentary view showing the foot of the support in its relationto the roof of the furnace jacket.

Figure 5 is a view in broken section of the furnace showing the positions of the two members of the booster trip during a normal operation of the furnace.

Figure 6 is a view similar to- Figure 5 but showing one of the members of the booster slide in its uppermost position with the other member in thelowermost position whereby both the check valve and the draft valve are kept in their closed positions.

Figure '7 is a view similar to Figures 5 and 6 but showing both of the members of the booster trip in their uppermost position for maintaining the check valve in closed position and the draft valve in open position.

The furnace I0 is provided withthe: usual jacket H and with a draft va1ve l2 and a check valve l3. The mechanism is designed for the purpose of automatically opening and closing the draft valve l2 and the check valve l3 in accordance with the fluctuations in the furnace heat. The 15 mechanism further contemplates the automatic control of the furnace heat through the draft valve l2 and the check valve I3 by means of a thermostat control in the living rooms.

The support for the mechanism is shown at'go M. This may consist of a single arm depending from the basement ceiling or itmay consist of a double arm as shown in Figure 4 or it may be made in any other suitable form. It extends to a position in close proximity to the roof of the 25 furnace jacket to which it is anchored as shown in Figures 1 and 4. The pin i5 is thrust through the roof of the furnace jacket and its exposed upper end portion is secured to the support I4 either before or after the insertion of the pin. 30-

An aperture is thus formed inthe roof of the furnace jacket but this aperture is entirely closed by the pin l5 so that no sand can enter the aperture. A control rod l6 also passes through the "roof of the furnace jacket but in this case it is 35' desirable that the aperture be large enough to permit the free sliding of the control rod. For this reason the aperture is made relatively large and it is surrounded by a sleeve I! through which the rod I6 is freely slidable as shown in 0 Figure 1. Since it is common practice to cover the roof of a furnace jacket with sand, the sleeve l1 must be of such a height that its upper extremity will be above the top of the sand so as to prevent the entrance of the, sand into the furnace. The rod l6. has its footing on the dome of the furnace l0 and it will be evident that it will respond to the movements of expansion and contraction of the furnace.

The lever arm I8 is pivotally secured to both the support l4 and to the control rod IS. The outer portion of the lever is considerably longer than the inner portion so that the movements of expansion and contraction of the furnace are transmitted to the outer extremity of the lever I8 in greatly amplified form. An increase of the heat in the furnace will therefore cause the depression of the outer extremity of the lever I8. In order to maintain the lower extremity of the control rod I6 always in contact with the furnace dome, we provide a counterbalancing spring I9 connecting the lever I8 to the support I4. The chain or similar flexible member 20 controls the movement of the draft valve I2 in response to the upward and downward movement of the outer extremity of the lever I8. Means 22 are provided for adjusting the chain 20 so as to secure proper movement of the draft valve at the desired temperatures. The connection of the chain 20 with the lever I8 will be subsequently described in detail. The arrangement, however, is such that when the draft valve is wide open the check valve is closed and when the draft valve is closed the check valve may or may not be open. Adjusting means 23 are also provided for normally maintaining the check valve in its proper open position to compensate for the leakage through the draft valve and other leakage at the front of the furnace.

Interposed in the control linkage is a double slide booster and trip which is best shown in position in Figure 1, the construction being best shown in Figures 3 and 6. This consists of a check valve slide 24 and a draft valve slide 25 which are slidable through an aperture in the plate 26 of the frame which is secured to the lever I8. The aperture in the plate 26 is such as to permit the free sliding movement of the slides 24 and 25 but which is sufficiently large to permit considerable angular movement between the slide and the lever I8. The forked lever 27 has an upper long tine which is pivotally secured at 28 and a latching tine 29. The check valve slide 24 is connected at its upper extremity to the chain 2| which controls the movement of the check valve I3. A short chain or link 30 is secured to the slide member 24 at its lower extremity and to the chain or link 3|] is secured a weight 3|. The weight 3| operating through the slide 24 tends to maintain the chain 2| in position to open the check valveI3. It is limited in its downward movement by the upper edge of a slot 32 in the slide member 24. This slot extends through about half the length of the slide member 24, its lower extremity being determined by the septum 33. The slide member 24 thus has a range of sliding movement determined by the upper and lower extremities of the slot 32. Such movement of the outer end of the lever I8 will tension the chain 20 to open the draft valve of the furnace. Downward movement of the outer end of the lever I8 will release the tension on the chain 20 to permit the draft Valve I2 to close under its own weight.

The slide member 25 has a range of movement throughout almost the entire length of the slide member 24 but it is normally in its uppermost position on the slide member 24 as shown in Figures 3 and 5. It also is provided with a septum 34 which is positioned in proximity to the lower extremity of the slide member 25. When it is in its uppermost position the tine 29 engages the lower edge of the septum 34 to latch the members 24 and 25 together. A chain 35 connects the slide member 25 to the chain 20 so that upward movement of the booster will be communicated to the chain to open the draft valve I2 and to close the check valve. A chain 36 is secured to the chain 2| and the'chain 36 is positioned for the convenience of the attendant of the furnace.

In order to prevent smoking when refueling thefurnace, the chain 36 may be manually actuated to apply tension to the lower portion of the chain 2| and to thereby lift the check valve slide 24 with its weight 3|. When the check valve slide 24 has reached its uppermost limit the tine 28 will enter the slot underneath the septum 33 to prevent downward movement of the slide 24. At the same time the pull on the chain 36 will cause a slackening of the chain 2| to permit the check valve to close. As the heat of the furnace rises the outer extremity of the lever I8 will be depressed and assume a greater and greater angle to the check valve slide which is normally held in vertical position by the weight 3|. When this angle increases to a predetermined magnitude the tine will be automatically disengaged from the lower edge of the septum 33 upon which the weight 3| will carry the slide member 24 downwardly to thus open the check valve I3. For magnifying the angular change between the booster and the lever I8 we provide an adjustable chain 31 which is secured to the chain 20 and trained under a pulley 38 on the lever I 8, the opposite end of the chain being secured at a fixed point 39. The pulley 38 is secured to a frame 26 which loosely embraces the lever i8 and which has considerable angular movement relative to the lever I8. Quite obviously the downward movement of the outer extremity of the lever is will cause greater and greater inclination of the forked lever 21, this inclination being an amplification of the inclination of the lever I8.

During the normal action of the furnace the parts are in the position shown in Figure 5 with the check valve slide 24 in its lowermost position and with the slide 25 in its uppermost position on the slide 24. When it is desired to refuel, ten-- sion is applied to the chain 36 which lifts the parts into the Figure 6 position with the slide 24 in its uppermost position and the slide 25 in its lowermost position on the slide 24. At this point the slide 24 is latched on the tine 25 bearing against the lower edge of the septum 33. Both the draft valve I2 and the check valve iii are closed. The check valve I3 should remain in closed position while the furnace is being refueled for the reason that smoke is apt to escape from the furnace during the refueling. After the refueling has been accomplished the check valve I3 may be opened manually, but the arrangement provides for the automatic opening of the check valve 3. If the attendant should forget it the automatic lowering of the outer end of the lever I8 will release the slide so that the weight 3| will cause the slide to drop and the check valve I3 to open. At times it may also be desired to provide for a slow increase in the furnace heat without opening the draft valve E2. When the check valve I3 is closed it ceases to counterbalance the slow leakage 'of air through the closed draft valve I2 and the fire can then burn more briskly than under normal conditions. In this case also the operation will be automatic to open the check valve I3 when the predetermined degree of heat has been reached.

The operation as thus far described is automatic except for the manual control of the check valve slide 24. Mechanism is also provided for automatically operating the booster in response to the room temperature and furnace heat. For this purpose we provide an electric motor 43 in an electrical circuit having a source of power 4| and having three switches. At 62 is shown a thermostatic switch which is automatically operaccuses able to close theswitch when the room tempera.--: ture falls below a predetermined minimum. At 43-is shown a switch which is adaiustably' operable through the means: 2? in response to. a predeterminedi minimum furnace heat. The; switch 43 isconnectedto the chain 2-10 at its upperextremity and it is provided with. two springsv which normally conterbalance each other. As the furnace. heat decreases, the outer end of the lever is rises and gradually releases'the. tension on the. chain 20. thus permitting the upper: spring to carry the switch lever 43 upwardly to close the. switch 43. The switches 42* and 43 are normally open as shown but they must both be. closed in order to start the action of the motor 40.. These switches are shown conventionally but. it is. to be understood that they may beof any type which is suitable for the purpose. The switch 44 is:

normally closed as shown, being held in closed position by a spring 45. When the room temperature and the furnace. heat both fall below their predetermined minimums the switches 42- and 43 will automatically close the circuit to start the motor- 40; The motor is provided with a. crank. 46 to which is secureda chain 41 with a nonwindingconnection as shown in Figure 2. The turning of the crank 46 through half a. revolution lifts the chain 41 and the entire; booster slide to a position where they will be latched as shown in Figure 7'. Further rotation of the crank46 will cause a slackening of the chain 41 above its connection with the booster but it will not permit the falling of the booster which is latched by means of the tine 29 against the underside of the septum 34. The rotation, however, continues since the switches 42 and 43 still remain closed. The crank 46 during its rotation contacts with the. switch 44 to draw it into the dottedlineposition of Figure 1. At this point. the contact isbroken to shut oil the. circuit and the parts remain in the dotted line position until the boosteris tripped when the outer end of the lever It has been depressed to a certain point. The release ofthe booster causes it to fall and carry with it the'crank 46 into the full line position of Figure 1. At this time the room' temperature may have. increased as well asthe furnace heat thus leaving the switches 42 and 43in their open position. After the crank passes the switch '44 the switch will be drawn back into closed position through the action of the spring 45. 'If' the switch 42 has not opened, the closing of the switch 43 will cause. succeeding cycles of motor action until the room temperature opens switch 42. The switch 43 is. opened and closed only by the expansion and contraction of thefurnace.

The importance of the cyclic operation is due to" the fact that the increase of heat in the furnace is apt to be more rapid than the flow of heated air from the furnace into the living rooms, thus resulting in a. condition in which the furnace becomes heat bound; While the air of the. living rooms is. below the predetermined. temperatures, the switch 42' will remain closed. The switch 44 is normally closed while the switch 43is responsive strictly to the furnace temperature. The result is that when the switch 43 is opened the draft valve I2 is closed due to the. fact that the motor .40 has stopped operation fol- I lowing the opening of the switch 43. The furnacehe'at then passes. out through the furnace pipes into the living rooms but at the same time the lever l8 rises at its outer end due to the loweringof the furnace heat. This will again. close the switch 43 which starts the motor on its next succeeding cycle- This will continue until the switch 42 is opened in response to a predetermined atmospheric temperature. of the living: rooms. At thesame time. the heated air is carried intermittentl-y to. the living rooms and is prevented from accumulating in the furnace to overheat the V furnace. In otherwords, atno time will the furnace. heat beyond a predetermined furnace temperature.

The switch 44 may be of any desired type, a plain contact. switch being shown in Figure 1 and amercury switchin Figure 2. The switch arm in the latter case is provided with a mercury: tube 48 which is set at such an angle that the:- switch is. normally closed and so' that the movement of the switch lever for a. sufficient disthe opposite end of the tube 48 to open the switch. l

It is often. convenient for the attendant of the furnace. to. beable'to determine the furnace temperatureand especiallyto determine the fluctuations in the furnace temperature following the operation. of the. furnace heat regulator. A simple thermometer as shown in Figural may be installed preferably in the front of the furnace jacket where it may readily be watched while the operator is-refueling-the furnace or clearing the grates. Such observation enables the attendant to. adjust the various parts with the greatest precision.

Having thusdescribed our invention in such full, clear, and exact terms that its construction and operation will be readilyunderstood by others skilled inthe artto. which'it pertains, what We claim as new and desire to secure by Letters Patent of the United States is: v

1 A support for a furnace heat regulator hav-'- ing mechanism including a lever for opening and closing the draft valve of the furnacein response to the movements of expansion and contraction of the furnace, said support consisting of a vertical member adapted to be secured at a fixed overhead position to depend therefrom, a prod for penetrating the furnace jacket, adjustable connections between said support and said prod for adjustment of the over-all length of said sup-- port and said prod, and means for maintaining tance will cause the drop. of mercury to flow to V said support and said prod in alignment, the arrangement being such that said support will be anchored against movement at both extremities thereof, said support being adapted to pivotally support the lever of the mechanism for opening and closing the furnace draft valve.

2. In a' furnace heatregulator, means responsive to both the furnace heat and the roomtemperature for automatically opening the furnace draft valvewhen both the furnace heat and the room temperature fall below i predetermined points, said means being automatically operable to close the furnace draftvalve when either the furnace heat alone or the furnace heat and the room temperaturerise'to the respective predeteiw mined points. I

. 3. In a furnaceheat regulator, means responsive to both the furnace. heat and. the room temperature. for automatically closing the check valve and for simultaneously opening the furnace draft valve when both the furnace heat and the room. temperature fall below predetermined temperature rise to the respective predetermined levels.

4. In a furnace heat regulator, means responsive to the movements of expansion and contraction of the furnace for moving the draft valve of the furnace toward open position, said means being automatically responsive to close the draft valve of the furnace when the furnace heat reaches a predetermined maximum level, and means responsive to both the furnace heat and the atmospheric temperature of a room for automatically opening the draft valve of the furnace, said last named means being automatically operable to close the furnace draft valve when both the atmospheric temperature of the room and the furnace heat reach the predetermined levels or when the furnace heat alone reaches its predetermined level.

5. In a furnace heat regulator, a lever having movement in response to the contraction and expansion of the furnace, a connection between said lever and the draft valve of the furnace for moving the furnace draft valve toward opening position when the furnace heat falls below a predetermined point, and a second connection between said lever and the furnace draft valve, said second connection having a sliding relation to said lever and being responsive to both the furnace heat and the room temperature to open the furnace draft valve when both the furnace heat and the room temperature fall below predetermined points, said second connection being operable to close the furnacedraft valve when the furnace heat and room temperature have both risen to their predetermined points.

6. In a furnace heat regulator, a lever having movement in response to the contraction and. expansion of the furnace, a connection between said lever and draft Valve of the furnace for automatically moving the furnace draft valve toward open position when the furnace heat falls below a predetermined point, a connection between the check valve and the draft valve of the furnace, and means responsive to the furnace heat and the temperature of a room for actuating said second connection to close the furnace check valve and to open the furnace draft valve when both the furnace heat and the room temperature fall below predetermined respective points, means for latching said second connection in the open position of the furnace draft valve and the closed position of the furnace check valve, said latching means being automatically releasable when the furnace heat and room temperature have both risen to their respective predetermined points.

7. In a furnace heat regulator, a lever having pivotal movement in response to the expansion and contraction of the furnace, flexible means secured to the draft valve of the furnace and adjustably secured to said lever for automatically moving the furnace draft valve toward open position when the furnace heat falls below a predetermined point, a flexible connection between the check valve and the draft valve of the furnace, said second connection having a sliding relation with said lever, a thermostat responsive to the atmospheric temperatures of a room, means responsive to said lever and to said thermostat for actuating said second connection to open the furnace draft valve and to close the furnace check valve when both the room temperature and the furnace heat have fallen below respective predetermined points, a latch for maintaining said second connection in the open position of the furnace draft valve and the closed position of the furnace check valve, said latch being automatically releasable when the furnace heat and the room temperature have both risen to. their respective predetermined points.

8. In afurnace heat regulator, a lever having pivotal movement in response to the expansion and. contraction of the furnace, flexible means secured to the draft valve of a furnace and adjustably secured to said lever 'for automatically moving the furnace draft valve toward open position when the furnace heat falls below a predetermined point, a flexible connection between the check valve and the draft valve of the furnace, means for manually actuating said second connection to simultaneously close the furnace check valve and open the furnace draft valve or to close the furnace draft valve and open the furnace check valve, said second connection having a sliding relation with said lever, a thermostat responsive to the atmospheric temperatures of a room, means responsive to said lever and to said thermostat for actuating said second connection to open the furnace draft valve and to close the furnace check valve when both the room temperature and furnace heat have fallen below respective predetermined points, a latch for maintaining said second connection in the open position of the furnace draft valve and the closed position of the furnace check valve, said latch being automatically releasable when the'furnace heat and the room temperature have both risen to their respective predetermined points.

9. A furnace heat regulator including a heat responsive member connected to the check valve of the furnace for operation, and manually set releasable means carried by said member for disengaging said member from valve operation and for releasing the check valve to assume its full closing position, said means being automatically releasable at a predetermined furnace temperature to open the check valve.

10. A furnace heat regulator including a heat responsive member,. a flexible member secured to the check valve of the furnace, a slip connection between said two members, said connection being manually operable to close the check valve and being automatically operable to open the check valve when a predetermined temperature has been reached in the furnace.

l1. A furnace heat regulator including a member responsive to. the furnace heat, slip connections between said member and the furnace check valve and the furnace draft valve respectively, one of said connections being manually operable to close the furnace check valve and the other of said connections being operable in response to atmospheric temperature and furnace heat to open the furnace draft valve, automatically operable means for opening the check valve, and automatically operable means for releasing the draft valve to closing position, said two automatically operable means being responsive to said heat responsive member and being adapted to function simultaneously or independently of each other at predetermined furnace temperatures.

12. A furnace heat regulator including a member responsive to the furnace heat, a connection between said member and the check valve of the furnace, manually set releasable meanscarried by said member for releasing the check valve to full closing position, said means being releasable at a predetermined furnace temperature to open the check valve, a second member responsive to atmospheric temperature, and connections between said first and second members and between said second member and the draft valve of the furnace for opening the draft valve when both the furnace heat and the atmospheric temperatures fall below predetermined limits, said connections being automatically operable to release the draft valve to closing position when both the furnace heat and the atmospheric temperature rise to the predetermined limits.

13. A furnace heat regulator including a heat responsive member and connections therefrom to the furnace check valve and the furnace draft valve respectively, manually set releasable means carried by said member for releasing the check valve to assume its full closing position, said means being automatically releasable at a predetermined fulrnace temperature to open the check valve, and automatically set releasable means carried by said member for opening the draft valve when the atmospheric temperature falls below a predetermined point, said last named means being automatically operable to release the draft valve to closing position when both the furnace heat and the atmospheric temper-' ature rise to the predetermined points.

14. A furnace heat regulator including a motor having a connection to the draft valve of the furnace for opening the draft valve and for releasing the draft valve to closing position, a member responsive to the heat of the furnace, a second member responsive to atmospheric-temperatures, said motor being connected to both of said members for automatic operation when both a the furnace heat and the atmospheric temperature fall below predetermined points, said motor and said first named connection having an automatic and intermittent operation for repeatedly opening the furnace draft valve and for releasing the furnace draft valve to closing position 

